/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package mj.ocraptor.extraction.tika.parser.xml;

import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

import org.apache.tika.exception.TikaException;
import org.apache.tika.io.CloseShieldInputStream;
import org.apache.tika.metadata.Metadata;
import org.apache.tika.mime.MediaType;
import org.apache.tika.parser.AbstractParser;
import org.apache.tika.parser.ParseContext;
import org.apache.tika.sax.EmbeddedContentHandler;
import org.apache.tika.sax.OfflineContentHandler;
import org.apache.tika.sax.TaggedContentHandler;
import org.apache.tika.sax.TextContentHandler;
import org.apache.tika.sax.XHTMLContentHandler;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;

/**
 * XML parser.
 */
public class XMLParser extends AbstractParser {
  private final org.slf4j.Logger LOG = org.slf4j.LoggerFactory.getLogger(getClass());

  /** Serial version UID */
  private static final long serialVersionUID = -6028836725280212837L;

  private static final Set<MediaType> SUPPORTED_TYPES = Collections
      .unmodifiableSet(new HashSet<MediaType>(Arrays.asList(MediaType.application("xml"), MediaType
          .image("svg+xml"))));

  public Set<MediaType> getSupportedTypes(ParseContext context) {
    return SUPPORTED_TYPES;
  }

  public void parse(InputStream stream, ContentHandler handler, Metadata metadata,
      ParseContext context) throws IOException, SAXException, TikaException {
    if (metadata.get(Metadata.CONTENT_TYPE) == null) {
      metadata.set(Metadata.CONTENT_TYPE, "application/xml");
    }

    final XHTMLContentHandler xhtml = new XHTMLContentHandler(handler, metadata);
    xhtml.startDocument();
    xhtml.startElement("p");

    TaggedContentHandler tagged = new TaggedContentHandler(handler);
    try {
      context.getSAXParser().parse(
          new CloseShieldInputStream(stream),
          new OfflineContentHandler(new EmbeddedContentHandler(getContentHandler(tagged, metadata,
              context))));
    } catch (SAXException e) {
      tagged.throwIfCauseOf(e);
      LOG.info("XML parse error", e);
      // TODO:
      // throw new TikaException("XML parse error", e);
    }

    xhtml.endElement("p");
    xhtml.endDocument();
  }

  protected ContentHandler getContentHandler(ContentHandler handler, Metadata metadata,
      ParseContext context) {
    return new TextContentHandler(handler, true);
  }
}
